Different subsets and/or polarized phenotypes of monocytes and macrophages may play distinct roles during the development and resolution of inflammation. Here, we demonstrate in a murine model of rheumatoid arthritis that nonclassical Ly6C(-) monocytes are required for the initiation and progression of sterile joint inflammation. Moreover, nonclassical Ly6C(-) monocytes differentiate into inflammatory macrophages (M1), which drive disease pathogenesis and display plasticity during the resolution phase.
View Article and Find Full Text PDFCaspase-8, an executioner enzyme in the death receptor pathway, was shown to initiate apoptosis and suppress necroptosis. In this study, we identify a novel, cell death-independent role for caspase-8 in dendritic cells (DCs): DC-specific expression of caspase-8 prevents the onset of systemic autoimmunity. Failure to express caspase-8 has no effect on the lifespan of DCs but instead leads to an enhanced intrinsic activation and, subsequently, more mature and autoreactive lymphocytes.
View Article and Find Full Text PDFAmyloid-beta related angiitis (ABRA) of the central nervous system (CNS) is a rare disorder with overlapping features of primary angiitis of the CNS and cerebral amyloid angiopathy. We evaluated a 74-year-old man with intermittent left sided weakness and MRI findings of leptomeningeal enhancement, vasogenic edema, and subcortical white matter disease proven to have ABRA. We discuss clinicopathological features and review the topic of ABRA.
View Article and Find Full Text PDFObjective: The mechanism responsible for persistent synovial inflammation in rheumatoid arthritis (RA) is unknown. Previously, we demonstrated that expression of the cyclin-dependent kinase inhibitor p21 is reduced in synovial tissue from RA patients compared to osteoarthritis patients and that p21 is a novel suppressor of the inflammatory response in macrophages. The present study was undertaken to investigate the role and mechanism of p21-mediated suppression of experimental inflammatory arthritis.
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